The invention relates to a method for making textured patterns on webs of fabrics, wherein the originally smooth web of fabric is first subjected to a mechanical pleating treatment.
In ladies' fashion pleated fabrics are constantly used to a lesser or greater extent--depending on the ever changing fashion trends--for further processing into skirts, dresses, blouses, etc. Mechanically pleated fabrics are used in particular, with fabrics being introduced lately--in addition to the so-called flat and upright pleats--which are provided with pleat patterns of different types instead of the evenly wide or deep pleats which run across the total width of a web of fabric. For example, such fabrics may be provided with wave-shaped pleats in addition to a plurality of small straight running pleats and in an alternating fashion wave-like pleats with adjacent straight running pleats, or adjacent to a short, small row of pleats, a similar row of pleats may be provided however offset by the half width of the row of pleats, etc. Such fabrics which may be called "irregularly pleated" are known, as well as the type and manner of their manufacture, whereby a plurality of further possible arrangements of irregular pleats exist and may be made in addition to the aforementioned pleat patterns. In comparison to clothes made from smooth fabrics the use of pleated fabrics of the aforementioned type has a substantially higher fabric consumption, depending on the type of pleats of the fabric to be processed, which naturally has a cost increasing effect on the clothes made from pleated fabrics. Furthermore, the processing of pleated fabrics into clothes is rather difficult and expensive, since constant care has to be taken from the initial cutting of the pleated fabric to the subsequent processing steps that the pattern of the pleats corresponds to the design, and that during the sewing of cut cloth pieces no tension is accidentally transferred to the fabric which would draw the pleats apart with respect to the intended design. In order to avoid this it is required to process a thin paper web which is placed beneath the web of fabric, at least when processing thin mechanically pleated fabrics.
It is, therefore, an object of the invention to provide a method for making webs of fabric which are texture-like patterned in the fabric material itself, in comparison to pleated fabrics, but which may be processed with a lesser consumption of fabric when making clothes and without the above-mentioned difficulties.
Furthermore, the inventive method should permit the partial printing of the web of fabrics with a color and/or a pattern which deviates from the base color, within the generated fabric texture.
Based on a web of fabric which has been subjected to a mechanical pleating treatment, this object of the invention is achieved by heating the mechanically pleated web of fabric and by deforming the heating pleats, whereafter the deformation of the pleats is fixed by cooling the web of fabric. Thus, the texture generated in the web of fabric is formed by the pattern of the deformed pleats. The deformation of the pleats is done differently, depending on the type of the initial pleat, however, in any case essentially in such a manner that at least a part of the fabric material which has been folded into the pleats is formed back into the plane of the web of fabric.
The partial printing of the web of fabric so that the printed areas are aligned with the textured pattern is carried out in a further embodiment of the invention wherein a web of thermal printing paper is fed onto the mechanically pleated web of fabric before the web of fabric is heated, wherein both webs are pressed together in a superimposed position while simultaneously heating the same to the temperature required for transfer of the ink and/or the pattern of the thermal printing paper onto the web of fabric, and that the web of thermal printing paper is removed after the pattern has been transferred onto the web of fabric. Advantageously, the fabric which is heated during the transfer printing process is immediately deformed, so as to eliminate an otherwise required reheating during the texturing process.
In fabrics having flat pleats the inventive method is preferably carried out in such a manner that the mechanically pleated web of fabric is so tensioned in the heated state that the pleats are substantially smoothed, whereupon the thus tensioned fabric is wound into a roll and is cooled in the wound-up state. Since the cooling of the web of fabric occurs in the wound-up state with pulled-apart pleats the pleats do not return to their original position during the subsequent processing but the fabric remains substantially smooth, while the pleat edges which were generated due to the heating and pressing effect during the initial pleating process remain as edge patterns which texture the web of fabric in the desired manner.
In the simplest manner the method may be carried out in that the mechanically pleated web of fabric which is still in a heated state from the pleat treatment is tensioned and wound up immediately following the heat treatment. Alternatively, the method may be carried out starting with a mechanically pleated web of fabric which is cooled and is present in form of a roll and in which the web of fabric is continuously drawn off from the roll and heated, tensioned again and then wound up again. For heating and tensioning and the subsequent winding up of the web of fabric a suitable calender having a heated roller may be used at which a winding up device with an adjustable winding up speed control is provided.
In this mode of the method it is also possible to print the web of fabric during the heating process in the transfer printing method in that the web of thermal printing paper is fed onto the mechanically pleated web of fabric which is drawn off from the roll before the continuous heating. The two webs are then pressed together in a superimposed position while simultaneously heating the same to the temperature required for transfer of the ink and/or the pattern of the thermal printing paper onto the web of fabric, and the web of thermal printing paper is removed from the web of fabric before the subsequent tensioning and winding up of the web of fabric. For the technical operation the aforementioned calender may be used again, but it must be provided with an additional receiving means for the thermal printing paper which has to be placed on the upper side of the pleated web of fabric to be printed, and should be provided with a winding up means for the thermal printing paper which has been used and which has to be separated from the web of fabric after the printing process.
If the inventive method is to be used in a web of fabric wherein first by mechanical means low upright pleats were pleated after being covered with an upper and lower web of paper, whereupon the pleated web of fabric is wound up and wherein the pleats were permanently fixed by a subsequent heat treatment of the roll, the inventive method provides that the web of fabric with the upright pleats and with the upper paper web removed, is drawn off from the roll and a web of thermal printing paper is placed onto it free upperside. Thereafter, the upright pleats of the web of fabric are partially compressed and engage with the compressed areas the web of thermal printing paper, while heat energy is applied to the rear side of the web of thermal printing paper which is facing away from the web of fabric, thus transferring the ink and/or the pattern of the thermal printing paper to the adjacent areas of the web of fabric. The thermal printing paper is subsequently separated from the web of fabric. Surprisingly it has been shown that during the partial compression of the upright pleated pleats no pleat squeezing occurs and that the compressed areas at which the thermal printing paper engages can be printed with a clear color print, while the width of the printed areas of the pleats may even be changed to a certain extent by varying the counter pressure of the thermal printing paper, so that more or less wide strip-like areas of the pleats may be printed, which results in particularly interesting effects when using monochromatic or multi-colored patterned thermal printing paper. Due to the heat applied during the printing process onto the areas to be printed the initially sharp edged fixed upright pleats are somewhat rounded off. Therefore, the texturing of the printed fabric is also referred to as "wave pleats."
When carrying out the aforementioned method preferably the upper web of paper is removed from the web of fabric before the heat treatment for the purpose of permanently fixing the upright pleats, and during the subsequent winding up operation of the pleated web of fabric a smooth following web of paper, i.e., one that does not engage the sides of the pleated upright pleats, is rolled into the web of fabric. The following paper web is again removed before applying the web of thermal printing paper.
A rational or economical mode of operation in the continuous pass-through operation is obtained if the web of fabric which is provided with the upright pleats and the web of thermal printing paper placed thereon is continuously fed onto the circumferential face of a rotating heated pressure roller, in such a way that the rear side of the web of thermal printing paper engages the pressure roller. The engaged webs are pressed against the web of thermal printing paper by a web of felt-like material which rest against the rear side of the web of fabric provided with the lower web of paper. The web of felt-like material winds around the pressure roller in a predetermined angle range and follows in this angle range with the angle speed of the pressure roller. The heat retaining web of felt which runs in the pressure range with the angle speed of the printing roller prevents a displacement of the web of fabric relative to the web of thermal printing paper, so that a clear print is generated. By changing the (relatively low) tension of the felt web the above-mentioned change in the width of the printed area may be adjusted.
As a material for the lower paper advantageously a web of creped paper is used which is a stiffer paper when compared with the paper which is used in the pure upright pleating. The crepe of the paper assures that no displacements occur between the web of felt and the lower paper web, while the increased stiffness permits generating the required minimum counter pressure of the web of paper onto the thermal printing paper so as to obtain a clear transfer print without the occurrence of a pleat squeeze.
In an advantageous further development of the invention the web of fabric with the provided upright pleats is tensioned in the longitudinal direction of the web prior to placement of the web of thermal paper, so that the upright pleats are somewhat pulled apart with respect to the non-tensioned state.
The finished printed web of fabric has lower, flatter waves when compared with a printing process without such an additional tensioning.
A similar effect may also be generated by separating the pleated web of fabric immediately from the lower web of paper after the printing and the removal of the web of thermal printing paper, and by winding up the same into a roll while still warm, under such a longitudinal tension that the wave-like pleats remaining in the web of fabric are smoothed in the wound-up state. A piece of fabric which is drawn off from this roll assumes again the wave shape. However, these waves are lower and wider when compared to a web of fabric which was wound up after the printing together with the lower paper in a non-tensioned condition. The consumption of fabric which depends on the pleat depth is considerably reduced when comparing the processing of pleated fabric with the processing of non-pleated fabric. In a borderline situation, i.e., when very flat waves are obtained the fabric consumption almost equals that of non-pleated fabrics.